title: Sedentary behaviours and obesity in adults: the Cardiovascular Risk in Young Finns Study.
abstract: OBJECTIVE
  Sedentary behaviour may contribute to the development of obesity. We investigated the relations between different types of sedentary behaviour and adiposity markers in a well-characterised adult population after controlling for a wide range of potential confounders.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  The Cardiovascular Risk in Young Finns Multicenter Study. Participants Sedentary time (TV viewing, computer time, reading, music/radio listening and other relaxation) was assessed with a questionnaire for 1084 women and 909 men aged 30-45 years. Other study variables included occupational and leisure-time physical activity, sleep duration, socioeconomic status, smoking, alcohol consumption, energy intake, adherence to the recommended diet, multiple individual food items, age and genetic variants associated with body mass index (BMI). Primary outcome measures BMI in kg/m(2) and waist circumference (WC in cm).
  
  
  RESULTS
  Of the different sedentary behaviour types, TV viewing was most consistently related to higher BMI and WC, both in men and women. One additional daily TV hour was associated with a 1.81±0.44 cm larger WC in women and 2 cm±0.44 cm in men (both p<0.0001). The association with TV was diluted, but remained highly significant after adjustments with all measured covariates, including several potentially obesogenic food items associated with TV viewing. The intakes of food items such as sausage, beer and soft drinks were directly associated with TV viewing, while the intakes of oat and barley, fish, and fruits and berries were associated indirectly. After these adjustments, non-TV sedentary behaviour remained associated with adiposity indices only in women.
  
  
  CONCLUSIONS
  Out of the different types of sedentary behaviour, TV viewing was most consistently associated with adiposity markers in adults. Partial dilution of these associations after adjustments for covariates suggests that the obesogenic effects of TV viewing are partly mediated by other lifestyle factors.
authors.affiliation: Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku, Finland.
authors.forename: I
authors.initials: I
authors.lastname: Heinonen
authors.forename: H
authors.initials: H
authors.lastname: Helajärvi
authors.forename: K
authors.initials: K
authors.lastname: Pahkala
authors.forename: O J
authors.initials: OJ
authors.lastname: Heinonen
authors.forename: M
authors.initials: M
authors.lastname: Hirvensalo
authors.forename: K
authors.initials: K
authors.lastname: Pälve
authors.forename: T
authors.initials: T
authors.lastname: Tammelin
authors.forename: X
authors.initials: X
authors.lastname: Yang
authors.forename: M
authors.initials: M
authors.lastname: Juonala
authors.forename: V
authors.initials: V
authors.lastname: Mikkilä
authors.forename: M
authors.initials: M
authors.lastname: Kähönen
authors.forename: T
authors.initials: T
authors.lastname: Lehtimäki
authors.forename: J
authors.initials: J
authors.lastname: Viikari
authors.forename: O T
authors.initials: OT
authors.lastname: Raitakari
keywords: EPIDEMIOLOGY; PREVENTIVE MEDICINE; PUBLIC HEALTH; SPORTS MEDICINE